Children's playgrounds and other recreational areas present opportunities for physical activity and challenge. Such areas often have equipment such as swings, slides, climbing nets and ladders. Because children can be expected to use equipment in unintended and unanticipated ways, playground equipment and their surrounding fall zones should be as safe as possible. The fall zone is the area under and around the equipment where protective surfacing should be present. For example, the fall zone for a slide is at least six feet from the perimeter of the slide with a possible larger fall zone at the front exit of the slide chute, depending on the height of the slide.
The Consumer Product Safety Commission has long recognized the potential hazards that exist with the use of playground equipment. A Commission study of playground equipment-related injuries treated in U.S. hospital emergency rooms indicated that the majority of injuries resulted from falls from equipment. Tinsworth, Deborah Kale, and John T. Kramer, Playground Equipment-Related Injuries and Deaths, U.S. Consumer Product Safety Commission, Washington D.C. (April 1990). These injuries were primarily falls to the ground surface below the equipment rather than falls from one part of the equipment to another part of the equipment.
Several different surfacing materials are currently used in play areas. Examples of such surfacing materials include asphalt, concrete, hard packed dirt, grass and turf, unitary synthetic materials and loose-fill materials. Unitary synthetic materials are generally rubber mats or the like. Loose-fill materials are materials such as wood mulch, sand, gravel or shredded tires.
These various types of surfacing material have different degrees of shock absorbency. Obviously, a fall onto a hard surface is more likely to cause a serious injury than a fall onto a surface with a higher degree of shock absorbency. Head impact injuries from a fall on any kind of surface have the potential for being life threatening. The more shock absorbing a surface can be made, the less likely the injury will be severe or life threatening. It should be recognized, however, that depending on the circumstances of the fall, an injury may occur even if a highly shock absorbing surface material is used in a recreational area.
Biomedical researchers have developed a testing method to determine when a head impact injury may be life threatening. This test evaluates the shock absorbing properties of a recreational area surfacing material. The test is performed by dropping an instrumented metal headform onto a sample of the material and recording the acceleration/time pulse during the impact. Researchers have established that if the peak deceleration of the headform during impact does not exceed 200 times the acceleration due to gravity (200 g's), a life-threatening head injury is not likely to occur. Handbook for Public Playground Safety, U.S. Consumer Product Safety Commission, Washington D.C. (1991) (hereinafter "Handbook for Public Playground Safety").
The term "critical height" is used to describe the shock absorbing performance of a surfacing material. It is defined as the maximum height from which the instrumented metal headform, upon impact, yields a peak deceleration of no more than 200 g's when tested in accordance with the procedure described in American Society for Testing Materials, Standard Specification for Impact Attenuation of Surface Systems Under and Around Playground Equipment, ASTM F1292 (Philadelphia, Pa.; May 1991) (hereinafter "ASTM F1292").
Table 1 gives the critical heights for various surface materials. The tests were conducted in accordance with the ASTM F1292 procedure.
TABLE 1 ______________________________________ Critical Heights (in feet) of Tested Materials Compressed Uncompressed depth depth Material 6 inches 9 inches 12 inches 9 inches ______________________________________ Wood mulch 7 10 11 10 Double shredded 6 10 11 7 bark mulch Uniform wood 6 7 &gt;12 6 chips Fine sand 5 5 9 5 Coarse sand 5 5 6 4 Fine gravel 6 7 10 6 Coarse gravel 5 5 6 5 ______________________________________
The Americans with Disabilities Act of 1990 ("ADA") prohibits discrimination on the basis of disability in employment, public services, transportation, telecommunications and public accommodations, including many services operated by private entities. 42 U.S.C. .sctn. 1210 et seq. It prohibits denying full and equal enjoyment of "goods, services, facilities, privileges, or accommodations" to disabled individuals with respect to any place open to the public. 42 U.S.C. .sctn. 12182. Existing structures, new construction, and alterations are all within the scope of the ADA's public accommodations provisions. Title III of the ADA includes within the definition of public accommodation: "a park, zoo, amusement park, or other place of recreation;" a school, including nursery schools; a day care center; and a gymnasium, health spa, or "other places of exercise or recreation." 42 U.S.C. .sctn. 12181. Public playgrounds, therefore, should be surfaced with a material so that physically challenged individuals may have access to playground equipment.
Hard surfacing material, such as asphalt or concrete allows recreational areas to be accessible to disabled individuals. These types of surfaces, however, are not otherwise suitable for use under and around playground equipment because of the high risk for injury due to a fall on the surface. Hard packed dirt is also not recommended because its shock absorbing properties can vary considerably depending on climatic conditions such as moisture content of the soil and temperature. It can be hazardous for children to play on very dry or frozen ground because of the lack of shock absorbance of these surfaces. Similarly, grass and turf are not recommended because their effectiveness in absorbing shock during a fall can be reduced considerably due to wear and environmental conditions. Handbook for Public Playground Safety.
Loose-fill materials such as sand and gravel are more shock absorbing than concrete or hard packed dirt, but these types of surfacing material have the disadvantage of inhibiting the maneuverability of wheelchairs, walkers, tricycles, bicycles, strollers and other wheeled items. Wheeled vehicles cannot easily move across sand and gravel. Further, the critical height values for sand and gravel materials decrease when the materials are compressed. Such compression can be expected from repeated use in high traffic areas of the playground. Also, moisture in sand can cause the critical height value for this material to decrease.
A disadvantage of unitary materials is that the material itself is very expensive. Unitary materials can be as much as ten times more expensive than the inventive surfacing material. Also, the ground underneath the synthetic material often must be made level and uniform before the unitary material is laid, which can be costly process. Further, this type of material may not drain well after storms because of puddles that may form on the surface. Another disadvantage is that synthetic materials can leach chemicals into the environment.